Environmental Protection Agency April 14, 2017 – Federal Register Recent Federal Regulation Documents

The Environmental Protection Agency (EPA) is proposing revisions pursuant to section 110 of the Clean Air Act (CAA) to the Federal Implementation Plan (FIP) addressing regional haze in the State of Montana. The EPA promulgated a FIP on September 18, 2012, in response to the State's decision in 2006 to not submit a regional haze State Implementation Plan (SIP); we are proposing revisions to that FIP. The EPA is proposing revisions to the FIP's requirement for best available retrofit technology (BART) for the Trident cement kiln owned and operated by Oldcastle Materials Cement Holdings, Inc., (Oldcastle), located in Three Forks, Montana. In response to a request from Oldcastle, and in light of new information that was not available at the time we originally promulgated the FIP, we are proposing to revise the nitrogen oxides (NOX) emission limit for the Trident cement kiln. We are also proposing to correct errors we made in our FIP regarding the reasonable progress determination for the Blaine County #1 Compressor Station and the instructions for compliance determinations for particulate matter (PM) BART emission limits at electrical generating units (EGUs) and cement kilns. This action does not address the U.S. Court of Appeals for the Ninth Circuit's June 9, 2015 vacatur and remand of portions of the FIP regarding the Colstrip and Corette power plants; we will address the court's remand in a separate action.

The Environmental Protection Agency (EPA) is announcing the availability of the final document titled Policy Assessment for the Review of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen (NO2 PA). Nitrogen dioxide (NO2) is the component of oxides of nitrogen (NOX) for which we have the greatest concern for public health. Accordingly, the current primary (health-based) National Ambient Air Quality Standards (NAAQS) for NOX are in terms of NO2. The NO2 PA presents considerations and conclusions relevant for the EPA's review of the primary NO2 NAAQS. The primary NO2 NAAQS are set to protect the public health from exposures to NO2 in ambient air.